This invention concerns a method for making naphthoquinone intermediates to known antimalarial and miticidal compounds.
Cross-coupling addition of organometallic reagents to certain organic halides, acetates, sulfonoxy compounds and the like is known. It is also known to catalyze such reactions, if necessary, with Ni(0) or Pd(0) complexes. However, it was not known heretofore that organometallic reagents can be cross-coupled to 1,4-naphthoquinones. Representative of the state of the art relative to cross-coupling addition reactions are the following.
Corriu et al., JCS Chem. Comm., 144 (1972) and Kumada et al., JACS, 94, 4374 (1972) disclose the nickel-catalyzed cross-coupling of Grignard reagents with halides.
Oku Rado et al., Tet. Letter, 12, 1027 (1978) disclose Pd(0) catalyzed alkenylation of bromocyclohexenone: ##STR1## where the Pd(0) catalyst=PdCl.sub.2 (P.phi..sub.3).sub.2 +i-Bu.sub.2 AlH.
Negishi et al., Tet. Letter, 3737 (1981) disclose Pd(0) catalyzed coupling of alkenyl halides with allylic aluminum and phenyl zinc, aluminum and zirconium reagents.
Negishi et al., JOC, 45, 5223 (1980) disclose Pd(0)-catalyzed coupling of .beta.-halo-.alpha., .beta.-unsaturated carbonyl derivatives with homoallylic zinc halides: ##STR2## where the catalyst can be Pd(P.phi..sub.3).sub.4 or PdCl.sub.2 (P.phi..sub.3).sub.2 +(i-Bu).sub.2 AlH.
U.S. Pat. No. 4,266,066 discloses reaction of aluminum alkyls with acid chlorides to yield ketones, optionally in the presence of AlX.sub.3 and in methylene chloride as solvent.
Stille, JOC, 44, 1613, 1979, reported reaction of acid chlorides with SnR.sub.4 (R=alkyl) in the presence of Pd(0) catalysts to yield ketones. The reaction occurs in the presence of a variety of functional groups including aldehyde.
U.S. Pat. No. 4,049,705 discloses preparation of 2-n-dodecyl-3-chloronaphthoquinone by reaction of 2-dodecyl-1-naphthol with sulfuric acid to give sulfonic acid, followed by chlor-oxidation with FeCl.sub.5 /H.sub.2 SO.sub.4.
Houben-Weyl, Methoden der Organischen Chemie, 7/3a, Chinone I, Vierte Auflage, pages 23 to 111 describes preparation of a variety of alkylnaphthoquinones.
U.S. Pat. No. 4,110,473 discloses preparation, from 2-alkyl-1-naphthol through 4-sulfonation, chlor-oxidation with chlorine and ferric chloride, and alkylation, of miticidal 2-alkoxy-3-alkyl-1,4-naphthoquinones.
U.S. Pat. No. 4,266,066 discloses reaction of acid chlorides with aluminum alkyls to yield ketones.